The W83193R-01 is a Clock Synthesizer which provides all clocks required for high-speed RISC or CISC microprocessor such as Intel PentiumPro , AMD or Cyrix. Eight different frequency of CPU and PCI clocks are externally selectable with smooth transitions. The W83193R-02/-04 also provides I2C serial bus interface to program the registers to enable or disable each clock outputs and choose the 0.6% or 1.5% center type spread spectrum. The W83193R-01 accepts a 14.318 MHz reference crystal as its input and runs on a 3.3V supply. High drive PCI and SDRAM CLOCK outputs typically provide greater than 1 V /ns slew rate into 30 pF loads. CPU CLOCK outputs typically provide better than 1 V /ns slew rate into 20 pF loads as maintaining 50 5% duty cycle. The fixed frequency outputs as REF, 24MHz, and 48 MHz provide better than 0.5V /ns slew rate.